This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. We have created a cheap, simple, small footprint chemostat array from commercially available parts. Using these chemostats, we can run 32 continuous cultures at once. This device is useful for physiology, experimental evolution, competitions, and fermentation optimization.